Supplemental material: Time trends in incidence, comorbidity, and mortality of ischemic stroke in Denmark, 1996-2016

Objective: To examine whether the incidence, comorbidity, and mortality of first-time ischemic stroke changed in Denmark between 1996-2016 overall and according to age and sex using a nationwide cohort design.

Methods: In this cohort study, 224,617 individuals >18 years admitted with first-time ischemic stroke between 1996-2016 were identified using Danish nationwide registries. We calculated annual age-standardized incidence rates and absolute 30-day and 1-year mortality risks. Further, we calculated annual incidence rate ratios using Poisson regression, odds ratios for 30-day mortality using logistic regression, and hazard ratios for 1-year mortality using Cox regression.

Results: The overall age-standardized incidence rates of ischemic stroke per 1,000 person-years increased from 1996 (2.70 [95%CI,2.65-2.76]) to 2002 (3.25 [95%CI,3.20-3.31]) and then gradually decreased to below the initial level until 2016 (1.99 [95%CI,1.95-2.02]). Men had higher incidence rates than women ...

目标：采用全国性队列设计（cohort design），探讨1996-2016年间丹麦首次缺血性卒中的发病率、合并症及死亡率在整体人群中以及按年龄和性别分层后的变化情况。

方法：本队列研究通过丹麦全国性注册数据库筛选出1996-2016年间18岁以上首次因缺血性卒中入院的224,617例个体。计算年度年龄标化发病率（age-standardized incidence rate）以及30天和1年的绝对死亡风险。此外，采用泊松回归（Poisson regression）计算年度发病率比，采用逻辑回归（logistic regression）计算30天死亡率的比值比，采用Cox回归（Cox regression）计算1年死亡率的风险比。

结果：缺血性卒中的整体年龄标化发病率（每1000人年）从1996年的2.70 [95%置信区间（95%CI）：2.65-2.76]上升至2002年的3.25 [95%置信区间：3.20-3.31]，随后逐渐下降，至2016年已低于初始水平（1.99 [95%置信区间：1.95-2.02]）。男性发病率高于女性……